[Comparison of five different ultrasonographic parameters for diagnosis of lethal fetal pulmonary hypoplasia].
OBJECTIVE
To evaluate the clinic value of five different ultrasonographic fetal parameters for prenatal diagnosis of pulmonary hypoplasia.


METHODS
Two hundred and seventy-one normal singleton pregnancies with well-established dates between 20 and 40 weeks of gestation were studied to establish normal reference range of five different ultrasonographic fetal parameters. The five parameters, which could reflect fetal lung mass, were as follows: lung area/body weight ratio, lung area, thoracic circumference/ abdominal circumference ratio, lung area/thoracic area ratio and lung area/head circumference. Thirty pregnancies with risk factors for pulmonary hyperplasia were studied for the usefulness of five parameters. Two or more standard deviations below the mean control group measurement were considered abnormal. The prenatal ultrasonic diagnoses of pulmonary hyperplasia were confirmed at neonatal follow-up examinations, on autopsy and by pathologic findings.


RESULTS
Lung area and lung area/head circumference increased with gestational age, lung area /body weight ratio decreased with gestational age. The relationships among the two ratios (thoracic circumference/abdominal circumference ratio, lung area/thoracic area ratio) and gestational age were relatively constant. Abnormal lung area/body weight ratio had a higher diagnostic accuracy than other parameters. Sensitivity of the parameters, including lung area, lung area/body weight ratio, thoracic circumference/abdominal circumference ratio, lung area/thoracic area ratio and lung area/head circumference were 83%, 97%, 50%, 70% and 87% , respectively. Sensitivity of the lung area/body weight ratio was 95% (20/21 fetuses); specificity, 9/9 fetuses; positive predictive value, 100% (20/20 fetuses); negative predictive value, 9/10; and accuracy 97% (29/30 fetuses).


CONCLUSIONS
Lung area/ body weight ratio is a good predictor of pulmonary hypoplasia.
Liang
Qin
Q
Department of Ultrosound, Second Xiangya Hospital, Central-South University, Changsha 410011, China.
Zhou
Qi-Chang
QC
Peng
Qing-Hai
QH
Zhang
Ming
M
Sun
Wei
W
Cao
Dan-Ming
DM
Ding
Yi-Ling
YL
D000328:Adult; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D005325:Fetal Organ Maturity; D005865:Gestational Age; D006801:Humans; D008168:Lung / Q000002:abnormalities* / Q000000981:diagnostic imaging* / Q000196:embryology; D011237:Predictive Value of Tests; D011247:Pregnancy; D012680:Sensitivity and Specificity; D013909:Thorax / Q000196:embryology; D013997:Time Factors; D018608:Ultrasonography, Doppler / Q000379:methods*; D016216:Ultrasonography, Prenatal; D055815:Young Adult